Armed police used batons and riot shields to separate the feuding asylum seekers. Order was not restored until 3.30am and 10 people needed hospital treatment for minor injuries.

The French had planned to bulldoze the camp, in a disused factory, in the early hours of yesterday and also to clear another site occupied by more migrants from Africa.

A week ago a court in Calais ordered police to raze the sites but the move has now been put back by the town’s police prefect, Denis Robin, who said: “I am taking time to see if there are solutions to this problem other than putting them out on the street.”

Meanwhile Mr Robin announced stricter security measures for the port and the introduction of all night surveillance to counter “the attractiveness of the port for migrants as well as people smugglers”.

Mr Mignonet revealed that 1,200 migrants are currently sleeping rough in outdoor camps or squats at the French port.

He said: “If the present disastrous state of affairs continues in Calais the port will be occupied by between two and five thousand migrants in a year’s time.”

He claimed anarchist activists like the group No Borders were worsening the problem and said people smugglers operating Europe-wide were making profits of billions.

He added that poorer migrants were finding themselves stranded in Calais because they were unable pay smugglers between £240 and £400 for a place in the back of a lorry on a ferry to the UK.

Mr Mignonet, 50, told the Daily Express: “Numbers of migrants arriving at Calais are rising massively with the arrival of waves of east Africans attracted to the UK via the Italian island of Lampedusa in the Mediterranean.

“Lampedusa is the point of entry into Europe for these people and Calais is the point of exit. The Italians have already indicated that they can’t cope with the situation and neither can we.”

He revealed that the mayor of Calais, Natacha Bouchart, is sending registered letters every day to the French President, Francois Hollande, the Prime Minister and the Interior Minister begging them for help.

He added that Madame Bouchart wrote to David Cameron at the end of June inviting him to come to Calais and “see for himself the problems the town faces” but has had no reply.

He said: “The mayor is very angry and frustrated. She has even said in the past that she would like to buy all the migrants tickets to the UK and load them into a ferry and dump them in England.”

The French say migrants are trying to get to the UK because of the benefits available to them in Britain.